How can I create a SEO friendly dash-delimited url from a string?

Question

Take a string such as:

In C#: How do I add \"Quotes\" around string in a comma delimited list of strings?

and convert it to:

Answer 1

A slightly cleaner way of doing this in PHP at least is:

function CleanForUrl($urlPart, $maxLength = null) {
    $url = strtolower(preg_replace(array('/[^a-z0-9\- ]/i', '/[ \-]+/'), array('', '-'), trim($urlPart)));
    if ($maxLength) $url = substr($url, 0, $maxLength);
    return $url;
}

Might as well do the trim() at the start so there is less to process later and the full replacement is done with in the preg_replace().

Thxs to cg for coming up with most of this: What is the best way to clean a string for placement in a URL, like the question name on SO?